It is approaching six months since Covid-19 vaccines were first approved for emergency use in the UK, with three different jabs currently in use.
The Pfizer, AstraZeneca and Moderna coronavirus vaccines are being rolled out across the UK, while other jabs are still pending approval from the Medicines and Healthcare products Regulatory Agency (MHRA), including Johnson & Johnson and Novavax.
The AstraZeneca vaccine is currently the most widely used coronavirus jab around the world.
A combination of a strict lockdown and a successful vaccination programme has seen Covid-19 cases steadily fall in the UK over the past few months, allowing some restrictions to be eased.
More than 43 million people have now been vaccinated against coronavirus in the UK, with 10.4 million having received both doses, and new coronavirus cases are averaging 35.707 per 1,000,000 people per day, according to the latest data up to 21 April.
Prime Minister Boris Johnson has credited the harsh lockdown for the reduction in deaths, infections and hospitalisations above the vaccination programme, saying the restrictions did the “bulk of the work”.
However, the vaccine rollout has undeniably helped in bringing infections down and the UK is still on track to offer all adults their first vaccine dose by the end of July.
But how does the situation in the UK compare to other parts of the world where the vaccine rollout has been strong, but Covid cases are high?
How is the vaccine rollout progressing around the world?
More than 950 million Covid-19 vaccine doses have been administered across the globe so far, according to the latest figures from Our World in Data, although it is still too soon to tell if the rollout is having an impact on reducing cases in some countries.
In the UK and Israel, which have administered 43.9 million and 10.4 million doses respectively, scientists have said the vaccines are starting to reduce deaths.
These figures show 48.83 per cent (UK) and 62.03 per cent (Israel) of the total population have received at least one vaccine dose. Our World in Data includes all age groups for this data, unlike the UK government which only counts people aged 18 and over in the population pool.
Both the UK and Israel are among the few countries to achieve high vaccination levels and falling death rates since the rollout began earlier this year.
However, the majority of countries have now managed to administer at least 50 doses for every 100 people, with this having the gradual effect of causing death rates to steadily decline.
The United States is currently leading the rest of the world in terms of vaccinations, having administered more than 215 million doses.
A total of 40.2 per cent of the population has now received at least one vaccine dose, and new coronavirus cases are now averaging 189.899 per 1,000,000 people per day, according to the latest data up to 21 April.
This is a significant drop from a daily average of 907.27 cases per day in early January.
Mainland China follows closely behind with 204 million doses, while India ranks third with 129 million doses, although this only accounts for 8.09 per cent of the population.
Brazil, Germany and Chile have also been successful with their vaccine rollout so far, administering 34 million, 23 million and 13.5 million doses respectively.
This amounts to 11.72 per cent (Brazil), 21.4 per cent (Germany) and 40.89 per cent (Chile) of the total population vaccinated with at least one dose.
Cases still high despite vaccinations
Despite the success of the vaccine rollout in some countries, high jab rates does not necessarily mean coronavirus cases are falling.
India is a key example as cases have surged in recent weeks, despite 130 million vaccinations being given, which amount to just 8.09 per cent of the population.
The country has reported more than 300,000 new coronavirus cases in a 24 hour period, the biggest daily total in the world since the pandemic began, with 314,835 new cases recorded on 22 April. The previous record was 297,430 cases, which was recorded in the US in January.
The cases have increased significantly since Wednesday (21 April) which saw 295,041 new cases reported, while the number of deaths rose over the past 24 hours by 2,104 to reach a total of 184,657.
The outbreak has left many hospitals overrun, while oxygen, drugs, tests and hospital beds are now in critically short supply in the worst affected areas.
The discovery of a new ‘double mutant’ Covid-19 variant in the country has been blamed as one of the main factors for the rising cases, while the surge in cases has also been linked to lockdown restrictions being eased two quickly.
Prime Minister Narenda Modi has come under fire for holding rallies without proper social distancing, while Hindu festivals have also been allowed to go ahead, including the Kumbh Mela gathering in Haridwar which has attracted around 25 million people since January.
Despite the rising cases, Prime Minister Modi said on Tuesday (20 April) that states should only enforce a strict lockdown as a “last resort”, stating that the focus should be on “micro-containment zones” instead, asking people to only step out “if necessary”.
However, a week-long lockdown has been imposed in Delhi, which started on Monday (19 April) night, with only government offices and essential services, such as hospitals, pharmacies and grocers, remaining open.
Chile has also struggled to bring coronavirus cases down, despite more than 13 million vaccinations.
High case rates and deaths have been attributed to the spread of the Brazilian Covid-19 variant, showing that infections can still surge if social distancing measures are relaxed too soon, despite an aggressive vaccination campaign.
The country reopened its borders in November and introduced permits for summer holidays in January.
But the lack of an efficient contact tracing system on people entering the country meant that infections were not quickly picked up, and as such, would have easily been spread as schools, shops and restaurants reopened.
This rising cases has meant the health system is once again overwhelmed and strict lockdown measures have been reimposed, while the country will need to vaccinate more of its population to help bring case rates back under control.
A similar picture can also be seen in Brazil, which has administered more than 34 million doses, but daily cases are still high at 375.043 per 1,000,000 people, based on data up to 21 April.
Again, the rapidly rising infections and deaths in recent weeks have been attributed to the Brazil Covid variant, but the country has failed to put a strict nationwide lockdown in place to curb the outbreak.
President Jair Bolsonaro has argued that the damage to the economy would be worse than the effects of the virus, and has even tried to reverse some of the restrictions put in place by local authorities in the courts.
Evidence suggests that countries need a combination of high vaccination rates and some form of social distancing measures to successfully bring infection rates and deaths down, and keep them down.
However, some countries may be recording a higher number of cases as the testing programme may not be as good as in other parts of the world.
In the UK, where testing is widely available, the current new daily case rate is very low at just 35.707 per 1,000,000 people.
Could there be a third wave in the UK?
Health experts have warned that the UK is likely to see a “summer surge” in coronavirus cases as lockdown restrictions are relaxed, sparking fears of a potential ‘third wave’.
Prof Adam Finn, of the Joint Committee on Vaccination and Immunisation (JCVI), said modelling indicates there will be a rise in cases as many adults have not yet been vaccinated.
He warned that the UK was still “vulnerable” and that the dates for lifting restrictions may need adjusting, despite the Prime Minister stating the lockdown roadmap will go ahead as planned.
However, Boris Johnson has said that most scientists were "firmly of the view" that there would be a third wave of the virus at some point this year.
Speaking to BBC Breakfast, Prof Finn, from the University of Bristol, said Mr Johnson was right to say the UK will see a further wave of Covid-19 cases, but there is still uncertainty over how bad the wave will be.
He explained that would depend on how quickly the vaccine rollout continues, and how many people come forward for vaccination, while people’s behaviour once restrictions are eased will also be a factor.
He said: “If people move too far forward with that too fast, we'll see things start to come up earlier.
"The sense that the problem is all over, I'm afraid is a flawed one, we're still in a vulnerable situation, and there are still significant numbers of people who potentially could be harmed by this infection if this happens."
A message from the editor:
Thank you for reading. NationalWorld is a new national news brand, produced by a team of journalists, editors, video producers and designers who live and work across the UK. Find out more about who’s who in the team, and our editorial values. We want to start a community among our readers, so please follow us on Facebook, Twitter and Instagram, and keep the conversation going.